[LAU] hardware - Intel CPUs

[david]

On 04/15/2014 03:17 AM, Len Ovens wrote:
>
> On Tue, 15 Apr 2014, James Mckernon wrote:
>
>> On Mon, Apr 14, 2014 at 2:06 AM, Len Ovens <len at ovenwerks.net> wrote:
>>       I would realy like to stay away from having to use a USB or FW
>>       audio IF. In fact I would like to be able to continue to use my
>>       delta 66 for as long as I can before I spend more money :)  The
>>
>> Thanks for the useful info in your post. Just to be clear on this
>> part: are
>> you saying you don't want to switch to USB/FW solely because you want to
>> keep using your delta 66, or because you have some definite preference
>> for
>> PCIe over USB/FW devices? If the latter, I wonder why?
>
> USB in audio is limited. Getting clear USB ports interupt wise is not
> easy. Audio can not be on a hub or share it's usb with anything else,
> but many new MB have no mouse or kb port so the USB is already being
> used for that much. The real reason though, is latency. With the pci the
> latency can be 1/4 what it can be in USB or FW. That is the lowest
> seeting jack for USB or FW is 64/2, but I can run the d66 at 16/2 with
> no problem on a well tuned system. This does make a difference for live
> work. I know that 64/2 seems like very good latency (it is) but remember
> that the card then adds another ms in each direction as well as the
> stage distances on top of that. That is the time it takes the sound to
> reach my ear after going through the computer as a processor and then
> through the air to my ear. Maybe that is still not worth worrying
> about... but even with 30 feet of cord and no digital delay, I can hear
> the delay from my playing to the sound reaching my ear.

Interesting. What is the difference between speed of sound in air and 
the speed of electricity through a cable?

I think the lowest I've had my UCA-202 (USB 1.1) card work at was around 
~3msec latency (on a USB2 port) with a Debian RT kernel just fooling 
around (no other RT optimizations on this 2.4GHz i7 laptop). I've had 
Yoshimi problems when latency gets too low on my stock kernel. And when 
I first tried Zyn, it had problems at much higher latencies than Yoshimi 
did at the time.

But I haven't done much music stuff with my new laptop.

-- 
David W. Jones
gnome at hawaii.rr.com
authenticity, honesty, community
http://dancingtreefrog.com